Documentation of the construction of electrical or electronic assemblies and systems is commonly accomplished with schematics, assembly drawings, parts lists and configuration logs. Schematics and assembly drawings are generated by drafting a design using either traditional manual drafting tools such as paper, pencil, triangles, squares, etc. or by modern computer aided design (CAD) software tools. Both of these methods result in drawings (illustrations and text) identifying the proper construction of electrical, electronic and mechanical subassemblies and assemblies. Parts lists or Bill of Materials are generally tabular information containing information such as the part number, description of the part, quantity of part used, unit of measure, source of supply and reference designated location of use. A configuration log is a parts list for a specific assembly potentially including identification information of the subassemblies contained within the assembly.
The purpose of a schematic is to illustrate the physical interconnection of components. The accuracy of a schematic may depend upon its use. An electrical schematic used to fabricate a printed circuit board needs to be very accurate for the circuit board to perform its intended function. On the other hand, a schematic for the wiring of a house may not need to be completely accurate for the wiring in the house to operate correctly because the electrician wiring the house can correct errors during installation.
The purpose of assembly drawings is to illustrate the mechanical assembly process and desired end result for the combination of several components. The accuracy of an assembly drawing also may depend upon its use. The architectural plans for a house may be very detailed when necessary to achieve a specific observable result, but may also be vague when details are left to the discretion of a skilled craftsman. For a high volume product produced by a factory, the drawings may need to be very accurate due to a company policy for documentation control or they may be allowed to be inaccurate when the factory has implemented other processes to correct the deficiencies. An assembly drawing will often contain instructions in addition to illustrations for clarity.
The purpose of the parts list is to identify the components required to produce an assembly. The parts list is often complemented with the schematic and/or assembly drawings to aid the assembler in achieving the desired result or end item. The parts list is typically correlated to the schematic by a reference designator which is an alpha-numeric string unique to the location of each part. The parts list is also typically correlated to the assembly drawing by either the reference designator or an item number which also uniquely identifies the location of each part.
The purpose of a configuration log is to record data such as serial numbers and parts numbers for subassemblies that make up an assembly. Manufacturers use configuration logs to record products shipped and shipping dates usually to identify the product's warranty period or collect data about customers buying habits.
The industry standard for defining reference designated location of use is ANSI Y32.16-1975. This specification provides a method for defining and utilizing uniquely identified locations for components, subassemblies, assemblies and cables, as well as standards for marking such items to aid in construction.
Documentation produced by these traditional means is often error prone due to the inability of disparate systems to fully inter-operate. Factories responsible for the construction of assemblies often require several cycles of correction to the documentation in order to improve its clarity, consistency and correctness.
These traditional systems may also be time-consuming and therefore costly. They are usually very general purpose and therefore require very detailed and careful input and checking, especially for consistency between systems. Since the quality of the documentation is entirely determined by the care of the drafter and checker, inconsistent, missing, and misleading or ambiguous results are common.
Traditional systems work well for documenting assemblies with limited configuration options. Conversely, these systems are not as efficient for documenting the assembly instructions for highly re-configurable or variable systems.
An accurate database of configuration information may benefit a customer when a repair for an assembly is required. The information contained in the database may be essential to the repair and not readily available from other sources. For example, a repair manual for a highly re-configurable assembly may simply not be able to identify all configuration options and corresponding repair procedures.
The present invention complements the traditional methods of documenting re-configurable assemblies by simplifying the creation of the variable portion of the documentation for assemblies with significant configuration options.